Microscopic World -1-
(Mysteries of Atomic World)
Part 2: The Structure of the Atom

It became clear
in Part 1
that the elementary
unit of matter
is an atom.
It also turned out
that electron is included
as one of the common
constituents of atoms.
This suggests that
the atom is not
an ultimate particle
but has
an internal structure.
Then we have
a question what the internal
structure of the atom is.
Let us enter
into the inside of an atom.